S.C. Code Ann. § 59-73-90

Each taxpayer when he pays any tax for school purposes voted under the provisions of Sections 59-73-40 and 59-73-50 may designate to which school in the school district he wishes the money paid by him to go, and the treasurer shall keep a note of such designation, and the money shall be applied as thus designated. When no designation is made by the taxpayer at the time of such payment the money shall be expended as other school funds in such district.